docs: reconcile spec inconsistencies across all documentation

- Fix incursion start day: 5→20 in GAME_BRIEFING.md (matches code constant)
- Fix fabricator discipline count: 2→5 in AGENTS.md
- Fix discipline counts: elemental.ts 22→21, advanced-regen.ts 14→15
- Fix equipment count: 50→43, remove shields, fix catalysts count
- Fix prestige upgrade count: add missing manaWell, manaFlow, pactBinding, pactInterferenceMitigation
- Remove x3 victory multiplier (no victory condition defined yet)
- Update pact persistence: pacts do NOT persist through prestige
- Update elemental matchup tables to match ultimate truth
- Update room type frequencies to match spire-climbing-spec
- Update guardian data tables to use formulas
- Update Tier 3 guardian elements to match guardian-data.ts code
- Add pactBinding + pactInterferenceMitigation to PRESTIGE_DEF constants
- Wire pactInterferenceMitigation into useGameDerived.ts
- Update spire-combat-spec.md Known Gaps table (DoT implemented, melee bypass bug)
- Update invoker-spec.md known issues (all resolved)
- Update golemancy-spec.md status (undergoing redesign)
- Update PrestigeTab test to expect 15 upgrades
- Create Gitea issues #285 (melee defense bypass), #286 (DoT verified), #287 (mana conversion gap)

src/lib/game/hooks/useGameDerived.ts

@@ -143,14 +143,16 @@ export function useCombatStats() {
     [activeSpell]
   );
 
+  const pactInterferenceMitigation = usePrestigeStore((s) => s.prestigeUpgrades.pactInterferenceMitigation || 0);
+
   const pactMultiplier = useMemo(
-    () => computePactMultiplier({ signedPacts }),
-    [signedPacts]
+    () => computePactMultiplier({ signedPacts, pactInterferenceMitigation }),
+    [signedPacts, pactInterferenceMitigation]
   );
 
   const pactInsightMultiplier = useMemo(
-    () => computePactInsightMultiplier({ signedPacts }),
-    [signedPacts]
+    () => computePactInsightMultiplier({ signedPacts, pactInterferenceMitigation }),
+    [signedPacts, pactInterferenceMitigation]
   );
 
   // DPS calculation